Selector for display board



May 2 1957 J. R. FRANCY SELECTOR FOR DISPLAY BOARD 5 Sheets-Sheet l Filed Feb. 17, 1964 TIM @n TIN wmm

BY HIS ATTORNEYS HA fafa/s, K/ECH, Russin. /l/ERA/ May 2, 1957 J. R. FRANCY 3,317,686

SELECTOR FOR DISPLAY BOARD Filed Feb. 17, 1964 5 Sheets-Sheet 2 FIG ZI l n 60 50 l l 1 l [|177/1 a/lu AHV/4 Inv/,1 59 fe; 59 m/f/ l l l l l A ,E I W W Il) l l IVILyll/ I l /J 50 65 ilo 'l i! die INVENTOR. JAMES R. FRANCY 8)/ HIS ATTORNEYS HABE/s, MECH, RUSSELL KERN May 2, 1967 J. R. FRANCY SELECTOR FOR DISPLAY BOARD 5 Sheets-Sheet 5 Filed Feb. 1'7, 1964 INVENTOR.

JA M55 R. FRA /vcy May 2, 1957 J. R. FRANCY K 3,317,686

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JAMES R. FRA/vcr BY HIS A7'7'0EA/EY5 #Ame/s, K/EcH, Russa/ L KERN May 2, 1967 1. R. FRANCY 3,317,686

SELECTOR-FOR DISPLAY BOARD Filed Feb. l?, 1964 5 sheets-sheet 5 EY H/S ATTORNEYS HAee/s, MECH, Russe/ 1. KERN United States Patent p 3,317,686 SELECTOR FOR DiSPLAY BOARD James R. Francy, Los Angeles, Calif., assignor to Scantlin Electronics, Inc., Los Angeles, Calif., a corporation of Delaware Filed Feb. 17, 1964, Ser. No. 345,326 8 Claims. (Cl. 200-46) This invention relates to selector systems and to circuit switching devices for use therein for coupling one of a plurality of inputs to one of `a plurality of outputs. The invention will be described herein as used in actuating a display module relay of -a security price display Ihoard such as is described in the copending application of Howard W. Beckwith entitled, Display Board, Ser. No. 219,260, tiled Aug. 24, 1962, and assigned to the same assignee as is the present appli-cation.

The selector of the invention receives as an input a multibit digital code representative of the individual characters of a stock symbol and functions to energize a relay of a particular display module of the display board, selecting such module for actuation by the incoming price data.

A typical display board will present vdata on several hundred stocks. The new price ldata for the various stocks is received serially and in random order. The selector system should provide for recognition o-f the stock symbol of the received data `and for connection of appropriate circuitry to an output corresponding to the recognized symbol. The selector system should also provide for changing of the stocks being displayed to accommodate changes in market activity and in -customer requirements. The selector system should be compact and reliable and should provide for manual selection and changing of stocks on display by non-technical personnel. These features .permit installation in a small yet readily accessible space so that the customer may make Ichanges in setting without the necessity of service calls by the installer. It is an object of the invention to provide a selecltor system meeting these requirements.

It is an object of the invention to provide a selector system for a stock display board or the like for actuating one of a plurality of switching devices in response to a particular input dode signal and manually changing the switching device responsive to such particular code signal and including a plurality of switching devices each having a plurality yof inputs each of which must be connected in circuit for actuating the switching device, a selector switch corresponding to each switching device input with each selector switch having an output for each switching device and an input for each character of the input code signal, a plurality of switch tabs for each .selector switch with eac-h switch tab providing a signal path Ibetween a desire-d selector switch input and a desired selector switch output and with each switch tab including means for manually changing the position of the switch tab wit-h respect to the selector switch to change the desired selector switch input and output, a switching matrix corresponding to each select-or switch with each switching matrix having an output for each input of the corresponding selector switch and a code input for controlling the mat- -rix switching operation and a circuit input for connection through the matrix, the selector switch and a ta-b -to a switching devi-ce input, with each of the switching matrices including means responsive to each input code signal for connecting the circuit input t-o a matrix output corresponding to the character of the code signal, and means for connecting the input code to each switching matrix code input in parallel.

It is another object of the invention to provide a selector for coupling selected input lines to selected output lines and including a plurality of circuit yboards with each of said boards having `an input circuit on one face and an output circuit on the other face, with the input circuit comprising a plurality of conductors disposed in parallel and with the output circuit comprising a plurality of conductors disposed in parallel and transverse to the conductors 'of the input circuit, means for mounting the boards in spaced parallel planes with opposed input and output circuits, and a plurality of slide tabs adapted for sliding insertion into the space -between adjacent boards in line with one of the conductors, each of the tabs including a terminal member projecting from opposing faces of the tabs for simultaneously engaging a conductor of the input circuit and a conductor of the output circuit.

It is an object of the invention to provide such a selector in which any number of circuit boards maybe utilized and in which the-circuit boards preferably are stacked in a stair-step sta-ck providing ease of access to each individual yboard and ease of insertion, viewing and removal of slide tabs from the spaces between each pair of boards. A further object is to provide such a structure incorporating a board terminal at an edge of .a board in line with each second conductor with each board terminal projecting past the edge of the adjacent `board and having a notch for receiving the edge of the adjacent board for controlling the spacing between boards.

It is another object of the invention to provide such a structure incorporating a board terminal having a slide tab receiving notch on one end and a tab engaging tapered boss projecting from the opposite end. An additional object is to provide such a structure in which the slide tab end is adapted for engaging the tab receiving notch and Iincludes an opening for simultaneously engaging the tapered boss of a terminal providing a detent retaining mechanism for the tab. A specific object is to provide such a structure in which the tapered Iboss has la slope of lesser angle with the terminal axis than slope of the tab receiving notch for urging the boss and tab opening into engagement as a tab is inserted into the board stack.

It is an object of the invention to provide a new and improved slide tab for use in the selector and incorporating a unitary terminal structure for simultaneously engaging a first circuit on one board and a second circuit 011 an opposing board. A further object is to provide such a structure in which the terminal may be positioned in any of a plurality of locations on the tab las desired.

While the selector will be described herein as used in conjunction with a stock display board, it should be noted that the invention is not limited to this single application. The invention also 'comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course. of the following description. The drawings merely show and the description merely describes a preferred embodiment of the present -invention which is given by way of illustration or example.

In the drawings:

FIG. l is a top view of a selector board stack incorporating the preferred form of the invention;

FIG. 2 is a sectional view taken along the line 2--2 of FIG. 1;

FIG. 3 is a sectional view taken along the line 3-3 of FIG. 1;

FIG. 4 is a partial sectional View taken along the line 4-4 of FIG. 3;

FIG. 5 is a top view of a slide tab;

FIG. 6 is an enlarged partial sectional view taken along the line 6-6 of FIG. 4;

FIG. 7 is a partial sectional view taken along the line r7 7 of FIG. 6;

FIGS. 8 and 9 are enlarged views of the upper left portion of FIG. 3 illustrating the detenting action of the tab and board terminals;

FIG. 10 is an enlarged partial sectional view taken along the line 10-10 of FIG. 1;

FIG. 1l is a top view of one of the circuit boards;

FIG. 12 is a view showing the mirror image of the bottom of the circuit board of FIG. 1l; and

FIG. 13 is a diagram illustrating the over-all operation of the selector system.

The system illustrated in FIG. 13 includes a fifteenbit shift register 20, three relay trees or switching matrices 21, 22, 23, three manual selector switches 24, 25, 26, and a plurality of module relay drive units, one of which is indicated at 30. A typical installation will utilize a hundred or more module relay drive units, one for each stock symbol.

In the :system described, the input signal is in digital form with a tive-bit character code received serially. The input signal on line 31 is Ifed into the shift register 20, providing storage of three characters forming a stock identification symbol. Twenty-eight characters are utilized, comprising the letters A through Z, Pr, and a blanlc The blank 'character is utilized where the stock symbol consists of only one or two letters.

The relay tree 21 is a switching matrix which provides for connecting the input at 32 to one of the twentyeight output lines 33. The relay tree may comprise tive relays driven by the first five flip-flops of the register and corresponding to the five bits of the code for the first character of the symbol. For each combination of energized and un-energized relays, the input 32 is connected to one and only one of the twenty-eight outputs 33. For example, suppose the character A is identified Iby the live-bit code 11000 and this code is stored in the register and connected to the relay tree. The first and second relays will be energized and the third, fourth and fifth relays will be de-energized thereby connecting the input 32 to the A output line.

The relay trees 22, 23 are identical to the relay tree 21, with the tree or matrix 22 actuated by the sixth through tenth flip-flops of the register and with the matrix 23 actuatedby the eleventh through fifteenth flipflops of the register.

Each of the manual selector switches is a multiple pole, multiple position mechanical switching device with a plurality of visual indicators identifying individual contact positions. There is a manual selector switch for each switching matrix, with the outputs of the switching matrix serving as the inputs for the manual selector switch.

Referring to the switch 24, each of the twenty-eight inputs is directly connected to a first circuit board 35. The switch includes an output 36 for each module relay drive unit with the outputs directly connected to another circuit board 37. A slide tab 38 provides an electrical connection between an input circuit on the board 35 and an output circuit on the board 37, in a manner to be deescribed below. There may be a slide tab for each output 36. The switches and 26 are identical to the switch 24.

The modeule relay drive unit includes a switching relay 40 and a module relay 41. The switching relay 40 has three inputs, one from each ofthe manual selector switches 24, 25, 26. When the input 42 of the switching relay 40 through the manual switch 24, the relay tree 21 and the input 32, and the switching relay input 43 is similarly connected through the manual switch 25 and the relay tree 22 to circuit ground at 45, the coil of the switching relay 40 will be energized to close the contact set 46. Then when the switching relay input 44 is connected through the manual switch 26 and the relay tree 23 to another negative supply iat 47, the module relay 41 will be energized. Hence the module relay of a particular :is connected to a negative supplyl drive unit is energized only when all three of the -drive unit switching relay inputs .are connected in circuit through the respective manual selector switches and relay trees. For any particular drive unit, the module relay 41 is energized only when three predetermined characters are in the register 20. By appropriately changing the slide tab 38 of each selector switch, any other cornbination of the twenty-eight available characters can be made to actuate the module relay 41 of the particular drive unit.

A manual selector switch is shown in FIGS. 1 through l2 and includes a plurality of printed circuit boards 50- -56 mounted in spaced parallel relation in a stair-step stack. Each board has a first circuit on the upper surface, as shown in FIG. 1l, which functions as the input circuit in the embodiment described herein. Each board also has a second circuit on the lower surface, FIG. 12, which functions as the output circuit in the embodiment described herein.

Spacer bosses 59 are positioned along the left edge of each board (as seen in FIG. 2), with the upper end of `a boss spun over in an opening in the board and with the lower end of the boss tapped to receive a screw. Spacer pins 60 are positioned between the boards engaging aligned openings in the boards, `as seen in FIGS. l and 2. Terminals 61 are carried on the board 50, being spun over in openings in the board and projecting upward therefrom. Similar terminals 62 are carried on the board 51 and project upward through openings 63 in the board 50. Similar terminals 64 are carried on the board 52, projecting through the openings 63 of the board 50 and similar openings of the board 51. Spacer terminals are carried on the -board 53, projecting upward through openings in the boards 52, 51 for fastening to the board 50 by screws 66. The boards 54, 55, 56 are provided with spacer terminals 65 in the s-ame manner as the board 53. The embodiment illustrated herein utilizes seven boards in the stack, with the top three -being identical, having the terminals 61, 62, 64 for wire connections, and with the remaining boards being identical and having the terminal 65 for screw connections. Of course, any number of boards may be utilized in the stack, and the commercial embodiment of the invention utilizes sixteen boards.

Referring to FIG. l1 which illustrates the upper circuit of a board, a conductor provides a circuit connection between a terminal area 71 and another terminal area 72, on opposite ends of the opening 63. By this means, the terminal 61 of board 50 is connected to the terminal 65 of the .board 53 and to the terminal 65 of the board 56. Similarly, the terminal 62 of the board 51 is connected to the terminal 65 of the board 54, and the terminal 64 of the board `52 is connected to the terminal 65 of the board 55. This arrangement permits these terminals of every third board to -be interconnected.

Referring to FIGS. 1 and ll, the input circuit on the upper surface of a board includes twenty-eight conductors 75 disposed in speed parallel relation, with a conductor corresponding to each input, here the letters A through Z, the symbol Pr and a blank. Means is provided for electrically connecting each of the conductors 75 to a corresponding terminal 71, the terminals being identified by characters adjacent thereto. This interconnection is achieved by means of feeder conductors on the lower side of the circuit board. Consider for example the input circuit for the character C. A terminal 61 is mounted over the terminal area 71 for the C letter, as seen in FIGS. 1 and 1l. The terminal 61 passes through the board (FIG. 2) and provides a direct electrical connection to -a corresponding terminal area 76 on the lower side of the board (FIG. 12). A feeder conductor 77 connects the terminal area 76 with another terminal area 78 which is positioned under the input circuit conductor 79 which is the C input. An eyelet or rivet 80 (FIGS. 1 and 10) is positioned in an opening 81 in the vboard and provides an electrical connection between the conductor 79 and the terminal area 78. E-ach of the remaining input conductors is connected to an input terminal by a similar arrangement.

Referring now to the output circuit, it should be noted that the illustration `of FIG. l2 is a mirror image of the lower side of a circuit board (except for the letters and numerals), which arrangement permits simultaneous viewing of the upper and lower surfaces of a board with the circuitry in register. The output circuit includes thirty conductors 84 disposed in parallel, transverse of the input conductors on the other side of the board. The particular embodiment described utilizes thirty output terminals per -board but the invention is not so limited and fewer or more terminals can |be used as desired.

A terminal 85 is provided at the left end of each output conductor 84, as seen in FIGS. 3 and l2. The terminals 85 are shown in greater detail in FIGS. 8 and 9. Each terminal is inserted through an opening in the circuit `board from the lower side, with the upper end of the terminal spun over or formed to lock the terminal in place and provide a tapered boss 86 projecting upward from the circuit board. The lower projection of the terminal includes a first notch 87, a second notch 88, and a third notch 89. The terminals preferably are formed as figures of lrevolution but can have other shapes if desired. The notch 89 is provided for making a wire connection to the terminal. The notch 88 engages the next lower circuit board to provide Iboth lateral and vertical spacing for the circuit Iboard stack. The first notch 87 includes a tapered section 90 for engaging a slide tab in a manner to be described below.

A plurality of side tabs is used with each manual selector switch, two being shown in FIG. l at 95, 96. The ta'b 95 is typical and comprises an elongate thin insulator adapted for sliding insertion into the space ybetween two circuit boards along a path defined by some of the spacer pins 60 and terminals 61, 62, 64, 65 with the tab in line with one of the conductors 84 of the output circuit on the lower side of a circuit yboard (FIGS. 3 and 4). When fully inserted, an end of the tab is exposed and may carry a letter or other identifying character on the upper surface.

Each tab carries an electrical terminal 97 providing an electrical path -between the output conductor 84 along the slide path of the tab and an input cond-uctor 75, the particular input conductor connected being dependent upon the position of the terminal 97 on the slide tab. A preferred form of terminal is shown in detail in FIGS. 6 and 7 and comprises a unitary member formed of resilient metal having a p-air of U-shaped portions 98 passing through a corresponding pair of openings 99 in the tab with a retainer pin 100 disposed in the U-shaped portions and passing `below the tab. The terminal 97 also includes resilient arms 101, 102 disposed on the upper side of the tab.

A terminal 97 is positioned in a particular pair of openings in the tab so that the U-shaped portion 98 will make contact with the particular input conductor 75 corresponding to` the pa-rticular identification character fixed at the end of the tab. In the embodiment illustrated herein, the tab 95 has fourteen pairs of openings disposed for providing contact withy fourteen alternate input conductors 7-5. The tab 96 is identical to the tab` 95 except that the fourteen pairs of openings are displaced one input conductor spacing so that a tab 96 configuration can be used for contacting the other fourteen input conductors.

The inner end of each tab is provided with an opening 105 for detenting engagement with the boss l86 of a terminal 85. Referring to FIGS. 8 and `9, as the tab is inserted into the space between the boards 50, 51, the inner end of the tab engages the slope 90 ofthe notch 87 of the terminal 85. Further inward motion of the tab causes the end to deect downward into the notch 87,

as seen in FIG. 9. The inward motion of the tab also Ibrings the opening into engagement with the tapered boss 86 of the next slower terminal 85. The angle b of the slope 90 with respect to the vertical is greater than the angle a of the tapered boss 86 so tha-t the distance between the slope 90 of the notch 87 and the tapered boss 86 increases for movement to the left as viewed in FIGS. 8 and 9. This arrangement provides a `locking detent for positioning and retaining the tab within the board stack.

A pair of spaced boards with an input circuit on the upper surface of the lower board and .an output circuit on the lower surface of the upper board together with one or more slide tabs corresponds .to one manual selector switch 24 of FIG. 13. This particular selector switch provides for twenty-eight inputs and up to thirty outputs, with a separate slide tab for each output. A stack of four b-oards functions as the three manual switches 24, 25, 26, each having twenty-eight inputs and up to thirty outputs, with a slide tab for each output in use. The stack of seven boards illustrated herein also functions as -the three manual switches 24, 25, 26, with each switch having twenty-eight inputs and sixty outputs. The inputs of every -third board are connected in parallel by means of the conductors 70 and the terminals 65, as described previously. One commercial form of the selector switch utilizes sixteen boards in the stack, providing three manual switches each having twenty-eight inputs and one hundred fifty outputs.

The slide tabs permit simple manual changing of the interconnections between the inputs and outputs of the selector switch. They also provide a direct visual indication of the setting of the selector switches. See for example FIG. 1 wherein a particular code is used to make the connections for the upper 130 outputs (where upper 30 refers to the output conductor 30 for the upper three boards of the stack as contrasted with lower 30 for the loutput conductor 30 of the next three boards of the stack). Here the customer desires to have the price data on the stock identiiied by the symbol AMO displayed on the particular display module which is energized from the upper 30 output terminals. To accomplish this, the user merely selects three slide tabs carrying the identification letters A, M and O and inserts them in the top three number 30 slots, as indicated bythe arrow of FIG. l. Slide tabs may be inserted for each of the remaining outputs in the same manner. Also, the connections can be changed at will by simply removing the slide tabs and inserting new tabs carrying the appropriate identification symbols. With a single letter or two letter stock symbol, a blank -tab providing a connection through the blank input conductor is utilized for the second and third or third character as required.

Returning to the AMO example, the input signal in the particular code utilized would be 11000 for A, 00111 for M, and 00011 for O. When this particular fteen- :bit input is stored in the register 20, the matrix 21 will be actuated to connect the input 32 to the A output line, the matrix 22 will be energized to connect the input 45 to the M output line, .and the matrix 2'3 will be energized to connect the input 47 to the O output line.

In the board stack corresponding to the switches 24, 25, 26, the actuation of the matrix 21 will connect the A input conductor of boards 51 and 54 to the input cir -cuit 32. Similarly, the actuation of the matrix 22 will connect the M input conductor of boards 52 and 55 to the input circuit 45 and the actuation of the matrix 23 will connect the O input conductors of boards `53 and 56 to the input circuit 47.

As a result of this action, every A slide tab in the space between the boa-rds 51, 52 and between the boards 54, 55 will provide the minus power from the input G2 to the input 42 of the switching relay 40 connected to the board output conductor contacted by Vthe slide tab. Similarly, each M slide tab in the space between the boards 52, 53 and in the space between the boards 5-5, 56 will connect circuit ground from the input 45 to the input terminal 43 of the connected switching -relay 40. At this time, all switching relays having an A connection at the terminal 42 and an M co`nnection at the terminal 43 will be energized.

All of the O slide tabs in the space between the boards 53, 54 .and in the space between the boards 56, 57 will provide a negative power connection from the input 47 to the terminal 44 of the contact set 46 of the switching relays connected to the board output conductors having the O slide tabs. The module relay 41 of the drive unit having the A, M and O slide tabs inserted as in the example will be energized. The module lrelays having all other combinations will not be energized. It should be noted that more than one module relay drive unit can be operated for a particular linput code by inserting more than one set of slide tabs with the same set of characters.

Although an exemplary embodiment of the invention has been disclosed and discussed, it will be understood that other applications of the invention are possible and that the embodiment disclosed may be subjected to various changes, modifications and substitutions without necessarily departing f-rom the spi-rit of the invention.

I claim as my invention:

1. In a selector for coupling selected input lines to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having an input circuit on one face and an output circut on the other face, said input circuit comprising a plurality of conductors disposed in parallel, said output circuit comprising a plurality of conductors disposed in parallel and transverse to the conductors of said input circuit;

means for mounting said boards in spaced parallel planes with opposed input and output circuits and defining a plurality of individual tab slide spaces therebetween;

a stop at one end of each of said slide spaces; and

a plurality of slide tabs, each separately and removably inserted into a slide space in line with one of said conductors,

each of said tabs including a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said input circuit and a conductor of said output circuit and means for adjusting said terminal member along the slide axis relative to the tab,

each of said tabs including an indicium on a portion of the tab projecting beyond a board when the tab is engaging a stop, with the indicium of a tab identifying the location of the terminal member thereon.

2. In a selector for coupling selected input lines to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having a first circuit on one face and a second circuit on the other face, said first circuit comprising a plurality of first conductors disposed in parallel, said second circuit comprising a plurality of second conductors disposed in parallel and transverse to the conductors of said first circuit;

mounting means for mounting said boards in spaced parallel planes with opposed first and second circuits and with each board offset with respect to the next board to provide a stair-step stack;

a board terminal carried at an edge of one board in line with a second conductor and projecting past the edge of the adjacent board, said terminal having a notch for receiving said edge of said adjacent board spacing said adjacent board and said one board; and

`a slide tab removably inserted into the space between boards in line with a second conductor, said tab including a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said first circuit land a conductor of said second circuit,

said tab having an end engaging said board terminal as a limit stop.

3. In a selector for coupling selected input lines to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having a first circuit on one face and a second circuit on the other face, said first circuit comprising a plurality of first conductors disposed in parallel, said second circuit comprising a plurality of second conductors disposed in parallel and transverse to the conductors of said first circuit,

each of said boards including first circuit feeder conductors on said other face disposed between second conductors, with a feeder conductor having a first teminal adjacent an edge of the board and a second terminal passing =through the board and connecting to a first conductor;

mounting means for mounting said boards in spaced parallel planes with opposed first and' second circuits and with each board offset with respect to the next board to provide a stair-step stack,

said mounting means including means defining a slide path in the space between adjacent boards in line with a second conductor;

a board terminal carried at an edge of one board and projecting past the edge of the adjacent board closing one end of said slide path, said terminal having a notch for receiving said edge of said adjacent board; and

a slide tab removably inserted into said slide path, said tab including a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said first circuit and a conductor of said second circuit,

f said tab having a first end for engaging said board terminal as a limit stop and an opposite end projecting from said stack and carrying an identification symlhol indicating the position of said terminal member in said tab.

4. In a selector for coupling selected input lines to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having a first circuit on one face and a second circuit on the other face, said first circuit comprising a plurality of first conductors disposed in parallel, said second circuit comprising a plurality of second conductors disposed in parallel and transverse to the conductors of said first circuit,

each -of said boards including first circuit feeder conductors on said other face disposed between second conductors, with a feeder conductor having a first terminal adjacent an edge of the board, a second terminal passing through the board and connecting to a first conductor, and a third terminal spaced from and electrically connected to the first terminal thereof;

mounting means for mounting said boards in spacedv parallel planes with opposed first and second circuits and with each board offset with respect to the next board to provide a stair-step stack,

said mounting means including a conductor boss joined to a first terminal of one board and to a third terminal of a remote board and passing through openings of intermediate boards providing a parallel electrical connection to the corresponding first conductors of said one and remote boards; and

a slide tab removably inserted into the space between boards in line with a second conductor, said tab including a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said first circuit and a conductor' of said second circuit.

5. In a selector for coupling selected input lines to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having a first circuit on one face and a second circuit on the other face, said first circuit comprising a plurality of first conductors disposed in parallel, said second circuit comprising a plurality of second conductors disposed in parallel and transverse to the conductors of said first circuit,

each of said boards including first circuit feeder conductors on said other face disposed between second conductors, with a feeder conductor having a fi-rst terminal adjacent an edge of the board, a second terminal passing through the board and connecting to a first conductor, and a third terminal spaced from and electrically connected to the first terminal thereof;

mounting means for mounting said boards in spaced parallel planes with opposed fir-st and second circuits and with each board offset with respect to the next board to provide a stair-step stack,

said mounting means including a conductor boss joined to a first terminal of one board and to a third terminal of a remote board and passing through openings of intermediate boards providing a parallel electrical connection to the corresponding first conductors of said one and remote boards, with adjacent conductor bosses defining a slide path between adjacent boards in line with a second conductor;

a board terminal carried at an edge of one board and projecting past the edge of the adjacent board'closing one end of said slide path, said terminal having a notch for receiving said edge of said adjacent board; and

a slide tab removably inserted into said slide path, said tab including `a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said first circuit and a vconductor of said second circuit,

said tab having a first end for engaging said -board terminal as a limit stop and an opposite end projecting from said stack and carrying an identification symbol indicating the position of said terminal member in said tab.

6. In a selector for coupling selected input lines to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having a first circuit on one face and a second circuit on the other face, said circuit comprising a plurality of first conductors disposed in parallel, said second circuit comprising a plurality of vsecond conductors disposed in parallel and transverse to the conductors of said first circuit;

mounting means for mounting said boards in spaced parallel planes with opposed first and second circuits and with each board offset with respect to the next board to provide a stair-step stack,

said mounting means including means defining a slide path in the space between adjacent boards in line with a 4second conductor;

a board terminal carried at an edge of each board and projecting past the edge of the adjacent board closing one end of said slide path, said terminal having a first tab-receiving notch and a second notch for receiving said edge of -said adjacent board,

said terminal including a tapered boss projecting from the opposite side of the board, said boss having a slope making a first angle with the axis of said terminal, -said first tab-receiving notch having a slope makinga second angle with said terminal axis greater than said first angle; and

a slide tab removably inserted into said slide path, said tab including a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said first circuit and a conductor of said second circuit,

said tab having an end for engaging said first notch of said board terminal and an opening for engaging said tapered boss for detenting said tab in position.

7. In a selector for coupling selected input lines, to selected output lines, the combination of:

a plurality of circuit boards, each of said boards having a first circuit on one face and a second circuit on the other face, said first circuit comprising a plurality of first conductors disposed in parallel, said second circuit comprising a plurality of second conductors disposed in parallel and transverse to the conductors of said first circuit;

mounting means for mounting said boards in spaced parallel planes with opposed first and second circuits and with each board offset with respect to the next board to provide a stair-step stack.

said mounting means including means defining a slide path in the space between adjacent boards in line with a second conductor;

a board terminal carried at an edge of each board and projecting toward the adjacent board closing one end of said slide path, said terminal having a first tabreceiving notch,

said terminal including a tapered boss projecting from the opposite side of the board, said boss having a first slope, said first tab-receiving notch having a second slope less steep than said first slope; and

a slide tab removably inserted into said slide path, said tab including a terminal member projecting from opposing faces of said tab for simultaneously engaging a conductor of said first circuit and a conductor of said second circuit,

said tab having an end for engaging said first notch of said board terminal and an opening for engaging said tapered boss for detenting said tab in position.

8. In combination: a selector for coupling selected input lines to selected output lines, said selector having a plurality of spaced circuit boards, each having an input circuit on one face and an output circuit on the other face, with the input circuit comprising a plurality of first conductors disposed in parallel and the output circuit comprising a plurality of second conductors -disposed in parallel and transverse to the first conductors; and a slide tab comprising:

an elongate fiat insulator removably inserted into the space ybetween adjacent boards in line with one of the second conductors,

said insulator having a plurality of spaced terminal opening means with each opening means corresponding to a first circuit conductor; and

a conducting terminal removably positioned in one of sai-d insulator opening means and including a resilient arm on one face of the insulator for engaging the second conductor, a U-shaped portion projecting through the opening means to the opposing face for engaging a first conducto-r, and a locking pin at said opposing face in said U-shaped portion.

References Cited by the Examiner UNITED STATES PATENTS 2,916,674 12/1959 Dix 317-112 3,223,957 12/1965 Cannon 339-18 BERNARD A. GILHEANY, Primary Examiner. T. MACBLAIN, Assistant Examiner.

UNITED STATES PATENT oFFIcE CERTIFICATE 0F CORRECTION Patent No 3, 317,686 May 2, 1967 James R. Francy at error appears in the above numbered pat- It is hereby certified th that, the said Letters Patent should read as ent requiring correction and corrected below.

Column 1, line 44, for "dode" read code column 4, line S8, for "speed" read spaced column 5, line 33, for "side" read slide column 8, line 18, for "temnal" read terminal column 9, line 49, for "circuit" read :Eirst circuit column 10, line 21, for "stack," read stack,

Signed and sealed this 21st day of November 1967 (SEAL) Attest:

EDWARD J BRENNER Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

1. IN A SELECTOR FOR COUPLING SELECTED INPUT LINES TO SELECTED OUTPUT LINES, THE COMBINATION OF: A PLURALITY OF CIRCUIT BOARDS, EACH OF SAID BOARDS HAVING AN INPUT CIRCUIT ON ONE FACE AND AN OUTPUT CIRCUT ON THE OTHER FACE, SAID INPUT CIRCUIT COMPRISING A PLURALITY OF CONDUCTORS DISPOSED IN PARALLEL, SAID OUTPUT CIRCUIT COMPRISING A PLURALITY OF CONDUCTORS DISPOSED IN PARALLEL AND TRANSVERSE TO THE CONDUCTORS OF SAID INPUT CIRCUIT; MEANS FOR MOUNTING SAID BOARDS IN SPACED PARALLEL PLANES WITH OPPOSED INPUT AND OUTPUT CIRCUITS AND DEFINING A PLURALITY OF INDIVIDUAL TAB SLIDE SPACES THEREBETWEEN; A STOP AT ONE END OF EACH OF SAID SLIDE SPACES; AND A PLURALITY OF SLIDE TABS, EACH SEPARATELY AND REMOVABLY INSERTED INTO A SLIDE SPACE IN LINE WITH ONE OF SAID CONDUCTORS, 